Marine speedometer.



C. H. KENNEY.-

MARlNE SPEE-DOMETER.

APPLICATION FILED MAY 9. 1913.

1 ,138,226. Patented May 4, 1915.

2 $HEETS-SHEET I.

Z8 lkliiwsscs l giaarlcs Eezzncy. I By his /ZZQI'M 132,062: for

C. H. KENNEY.

' MARINE SPEEDOMETER.

APPLICATION FILED MAY 9, 1913.

1 ,138,226. 1 Patented May 4, 1915,

2 SHEETS-SHEET 2.

280s Wiinessans; fnufiilfdf: g gmzw, I U/aarles E/remw W3 MW WM CHARLESH. KENNEY, OF NEW LONDON, CONNECTICUT.

MARINE SPEEDOMETER.

Specification of Letters Patent.

Patented May 4, 1915.

Application filed may 9, 1913. Serial No. 768,490.

To all whom it may concern Be it known that I, CHARLES H. KENNEY, acitizen of the United States, residing in New London, in the county ofNew London and State of Connecticut, have invented certain new anduseful Improvements in Marine Speedometers, of which the following is, aspecification.

My present invention relates to marine speedometers or automaticrecording logs for "essels, adapted to continuously indicate and record.the ships general direction (ahead or astern) and approximate speed, andconsists in certain improvements, as hereinafter described, upon theapparatus illustrated anddescribed in my pending application, Serial No.634,881, said improvement being designed to make such apparatus moregenerally and readily applicable to different locations upon vessels ofvarying types, and more accurate and re iable in practical v operation.

As in the application referred to, I provide, on avessel, a suitableeXhauster-blower or reversible air pump connected with the engine or .apropeller or wheel-shaft, a

I glazed case, an air pipe connecting said air pump with said case, avane or blade operable by air pressure or suction induced by said pump,a pointer or needle connected with said blade, a dial by which to readlocations of said pointer, a clock and a tape-record mechanism operablyconnected with said clock and blade or vane.

The entire apparatus constitutes an automatic reading and recording log,which, by

" means of the location or dip of the pointer em follows: 7

(and the reading thereof on the dial), reads at a glance whether theships engines are at rest, moving normally, or reversed, and theengine-speed; and which continuously draws on the tape a time, speed anddirection diagram which records all starts and stops and reversals ofthe engines and the time thereof, their approximate speed and theperiods during which such speeds were maintained.

The case containing the dial and taperecord mechanism may be located inany of similar cases various partsof the yessel andconnect all" of themwith onejair ied int is application are-genera as part of the'vessel. Imay locate a plurality and-pi e-system.- The novel fe gggres dials andtapes right handand left hand, bifurcate the air ducts in the case andprovide right-hand and left-hand pipe connections on the case, so thatby using the proper dial and tape and properly connecting the air pipeto the case, it can be hung to face either to port or to starboard andalways have Ahead on the dial read toward 'the bow and Astern toward thestern of the vessel. These characteristics render my log much moregenerally applicable and useful. Many ships have a plurality ofpropeller shafts; and such shafts are generally disposed and oppositelyrotated, in pairs. My present apparatus canbe connected with any suchshaft without regard to which way it turns, and the cases can be locatedat will, provided only that the air pipe be connected with each case bythe proper inlet, and the proper kind of dials and-tapes be used (rightor left hand). It will be seen that my improvements enable me tostandardize my apparatus and make one general type and pattern,adaptable to all conditions and locations, the only differences beingthat some will require right hand and some left-hand 'dialswrn tapes,and some will be connected with the ir by the left and some by the righthand )ipe connection. Moreover, these qualities enable me to locatecases close to the steering wheels; because bridges and pilot-houses ofvessels should not be illuminated at night, and when so hung my logrequiresthe minimum illumination, merely enough to enable night use insuch places are that the case and dial be practically invisible and thepointer barely visible, indicating, .by its verticality or dip towardbow or stern, whether the engines are at rest, going ahead or reversed,and by the degree of dip their approximate speed; whichan experiencedman can read practically as well without as with a dial. It is obviousthat the (lBSiI'BdillllIlllIlfitlOIl of the pointer can, beObtainedimthpnt rendering theldial and-other vparts"v slbl'e, byas'u1tably-arranged lamp and reflector, or by luminouspainti y i (b Myimprovements enable me to hermet'fcally seal the ease and keep dirt anddamp out of it and away from the indlcator and rec ord mechanism, andthugzn alge the suitably paint ng the. -:pointer, i,as .with a p no Ilog more delicate and precise and at'the same time more durable andreliable in its operations.

(c) I provide independent and independcntly adjustable spring gages orresistances for Ahead and Astern motions of the mechanism. Numeroustypes of ship engines, especially turbines and explosion engines,function in one mode when going ahead and-inan entirely different modewhen reversed; and my improved construction enables me to so adjust myapparatus to such engine-modes as to give my log the greatest possiblerange and convenience in use.

.(d) I have greatly improved the modes of mounting, inserting and removig, and driving the tape and the mode of operating the tracing point orpencil.

(e) I make it more convenient for use by adding a clock dial."

In the drawings, Figure 1 is a front elevation with the face plateremoved. 'Fig. 2

is a section on the line 22 of Fig. 1; Fig. 3 is a detail of the pencilslide-way; Fig. 4 is an enlarged detail of the pencil carriage; and,Fig. 5 is a detail of the contact plate of the spring gage.

I As in the application referred to, I pro-.

vide a case 1, preferably made of cast' metal, a face plate 55 suitablysecured (preferably screwed) thereto and making a tight joint therewith,and glazed openings 56, 156 and 157 in the face plate for readingrespectively the log dial, the clock dial and the tape record. In thecase 1 I core or otherwise form two air-ducts 28 and 28 each having anexterior nipple or socket 280 and 280 adapted for the connection of anair pipe, by threading, or in any other convenient manner, andconnecting freely attheir inner ends with a cylindrical sector or curvedbore 29, whose cap plate 37 is detachably secured air-tight by screws,to the walls of the air duct, whose cross-section is substantiallyrectangular and whose interior surfaces are suitably finished to co-actwith a blade or vane 36 pivoted in the axis of the cylin.- dri'cal wall,30, of said sector, on a shaft, 26, rotatably mounted in bearings, oneof which is formed in the back wall 35 of the case 1 and the other,through which said shaft extends, in the cap 37. Above and concentricwith said axis, I mount a segmental, graduated and reading indicatordial A, adapt- .ed by suitable graduations, divisions and legends to beread with a needle or pointer, 25, fixed on the shaft 26 and oscillatedthere- 'with and with the. vane 36 by variations in thftehsion of theaircontained in or passing throughthe ducts 28 and'sector 29, saidtenslonv'ariations being caused by the action of the aforesaid airpumpconnected with the en ne, preferably .with a propeller shaft.

11 the aforesaid application I show but one such duct connected with thesector, whose opposite opening communicates freely with the interior ofthe case 1. In the practical use of my log I have found thisconstruction to be open to criticism, as involving changes in morecostly parts of the apparatus in order to best adapt it to its uses andalso because dust and damp were brought into the case by the air andimpaired the mechanism therein and its operation. I found it highlydesirable that the dip of the pointer corresponding with normal enginedirection and also with the location of Ahead on the dial and on thetape, should always be toward the bow and the opposite dip and the dialand tape-legends Astern should always be toward the stern, in order thatreadings might be taken instantane ously and always surely, withreference to the bow and stern of the ship itself and to the vertical,and in bad lights or in darkness.

I early found it highly desirable to provide lefthand and right-handdials and tapes so that logs facing to port and to starboardrespectively should both have the Ahead legends toward the bow and theAstern toward the stern; but in order to make the dips of theirrespective needles correspond with their" legends, I found it necessaryto provide two air pumps oppositely geared to the engine, two sets ofair pipes, or some other costly and objectionable means of properly andsimilarly moving the oppositely-facing pointers. My present or- Iganization accomplishes all the desired results in a. cheap and unobectionable manner.

Having provided the two ducts 28 and 28* each with its nipple or socket280 and 280*, when the log faces ahead or port, I connect the air pipewith the left-hand duct 28 and nipple 280 and when it faces starboard orastern, I connect the air pipe with the right-hand duct 28 and nipple280'. By this organization I always locate the positive pressure side ofthe vane 36 toward the stern and its negative pressure or suction sidetoward the bow, or toward starboard and port, respectively, when theapparatus iia ces fore or aft.

The two air nipples, 280 and 280 are illustrated as one in front of theother, in the axial plane of the case 1, but obviously they could belocated in any convenient place, so long as they are individual. It willbe ob servedthat the ducts and sector do not communicate with thecasing, theonly opening in their walls being that filled by the shaft26. Therefore air entering one, of the nipples passes through said ductsand out by the other nipple, and cannot convey dirt into the interior ofthe ease to foul or clog the parts therein.

,In the application referred to, I use an adjustable jack-knife springarrangement to' locate the pointer vertical when the engines rest andwhich constitutes the gage or installed with turbine or explosionengines (because their modes of action vary with their direction ofpropulsion) a single gage apparatus could not be conveniently madesatisfactorily adjustable both for normal and reverse engine-rotation. Ither efore provide independent gage levers, 50, jindcp'endentlypivotally mounted, preferably oppositely, and independently adjustable,

each by a set screw. working in a threaded I hole in a frame member 1and each comprising an upright arm 49 and a horizontal arm 51, one ofsaid arms being a plate spring and one engaging a flat surface, 48, onthe shaft 26. It is obvious that the angle included between said arms isimmaterial, as is also their location ,relatively to one another; andthat this type of gage may be replaced by any other without aifecting myinvention. The essential organization is, two independent spring gagesconnected with the Vans 36 and substantially free from strain when thepointer is neutral and one of which acts and the other rests when thepointer dips positively and vice-versa when 1t dips negatively.

In order to make the gage action more is positive and delicate, byeliminating un-' necessary friction, I offset the active end of the arm51 and rivet or a hardened andpolished steel contact plate 51 whichbears on the fiat 48. I found it desirable to provide a clock-dial sothat the time, direction and approximate speed might be read by oneglance at the log. I therefore raise the clock work above and adjacentto the dial and provide a clock-dial13 a corresponding glazed opening,56, in the face plate 55, a gearing 14 connecting the clock mechanismwith the tape feed gearing 18 of the tape feed roller 15, and a clutch14 by means of which the gearing'may be promptly disconnected when a newtape 4 is tobe inserted. The connecting gearing comprises a geartrain-14 revolubly mounted on the case 1, a pair of bevel gears, 14, oneattached to the final gear of said train and its mate fixed on avertical shaft, 14, revolubly mounted in bearings formed in frames 1 bycollars 14 fixed to said shaft between and adjacent to the upper pair ofsaid supplemental frames, and a pair of bevel gears one, 14, revolublymounted on the vertical shaft 14 adjacent to its lower end and its mate14 fixed to the shaft 18 of the tap feed gearing 18. a

The clutch 14? is a friction clutch comprising a friction cone 14* onthe vertical shaft 14 engaging it slidably by a spline 14 and adapted toengage a corresponding socket 14 in the lower bevel gear 14 when presseddown by a spring 14 strained between said friction cone 14 and a collar14 fast on the shaft 14. The bevel gear 14 is supported on the shaft 14by a collar 14.

A disengaging clutch lever 14 is pivotally.

ficient to keep the tape taut is produced by the pressure of aroll-spring, 4 which is adjustably secured ,to an arm 1", pressesagainst the tape roll 4 and is adjusted by a screw 4. The tape 4descends outwardly inclined to and across a marking table M and thencesubstantially vertically to and between the feed rolls. causes the tapeto lie smoothly on arid in contact with said marking table whatever theamount of tape on the roll, the only effect of use of tape from the rollbeing to increase the angle of its descent to and its pressure againstthe table.

Two feed .rolls, 15 and 15, elastically pressed together and grippingand pulling the tape 4 when they are revolved, are revolubly mounted byjournals in suitable bearings in a frame 1 attached to the case 1 andpositively geared together by feed' gears 18"; although they wouldoperate satisfactorily if not so geared. The lower roll is axial withand angular-1y fixed relatively to the feed-gear shaft 18 and revolubletherewith by the cldck mechanism and the gearing's 14 and 18. Thediagrammed tapepiles in the bottom of thecase 1, whence it may beremoved when desired, and new tape in- This arrangement" and withoutvariable elements; .and therefore the record is much more precisely andaccurately diagrammed, and the unwound tapes are easier to compare,check up with other records, amLfile. Removal of used and insertion ofnew tapes can be readily accomplished by removing the face plate 55,

swinging out the marker frame lVI and the parts mounted on it, liftingthe clutch cone 1 t turning by hand thetapefeed rolls to advance andfree the last of the used tape and removing it; lifting out the emptyand mounting a fresh tape roll i in the slots of the frame 1, en aging'the free end of the fresh tape with the feed rolls 15 and 15 and drawingit taut, and reengaging the clutch 14: and replacing the face plate 55..j

In my aforesaid application I show marking apparatus comprising a markerfixed on a bar slidably mounted in guides formed in the heads of twoplugs inserted into and spring-positioned in sockets: bored in postsattached to the case, the bar: being reciprocated with the oscillationsof the vane and pointer by a hinged-lever connection with their shaft. Ihave improved my marking apparatus and adapted it to satisfactory use inconnection with a record "tape mounted and fed as set forth abovefQMyimproved marking apparatus M comprises generally, a marking table Mfixed to "and extending transversely across the caseil below andsomewhat in advance of the: anterior limb of the tape roll 4 so thattape drawn from said roll inclines outwardlyto reach and pass across,and is drawn taut over, said table, and a unital marker frame M locatedin front of the tape and markingtable M somewhat higher than andgenerally parallel with the latter and which is hinged to the case 1 atone end by a hingeM and detachably, preferably snap-connected thereto atthe other, provided with parallel guides M for slldably mounting themarker carriage 74, and a mounting arm M onQwhich I pivot the markerlever 60. The parallel guides M are preferably formed on the face of theframe Ni and on a bar Mfparallel and screwed thereto at its ends and themarker carnage 74 lies between said frame and bar and engages saidslides on the guides thereof. The carriage 74: carries a ma'rfljrer orpencil 75 and locates it exterior and perpendicular to the tape 4 andtable IVI against which it s pressed by a spring 74; said marker beingpreferably a point of penctlglead, mounted in a bore formed in a head,E4, of the carpage 7 and fed out by said spring, which is confined in asocket 74 in said head, and between the cap, 74:, of said socket and apiston, 74:, therein, against whichf'the pencil 75 abuts.

In my pending application the pointer and the marker move synchronpuslybut in opposite directions, so that like legends on the tape and on thedial are on opposite sides of their common vertical 1 ractice provedthis to sometimes lead-Ito confusion and showed the deslrabihtyofjalways having things of like meaning in like general locations. Itherefore provide a. like-moving operable connection 60 between thevaneand-pointer shaft 36 and the marker carriage so that a dip of thepointer 25 and a traverse of the carriage 74: are always synchronous andlike in general direction. Said connection preferably comprises a spurpinion 260 on the shaft'QG and a lever 60 pivoted on the marker-framearm 11, having its upper arm formed of a wheel segment 60 normallyengaged with the pinion 260 and in its lower arm a slot 61 engaging apin 62 projecting outwardly from the carriage 74.

When the shaft 26 is rocked by unequal air-tensions on the sides of thevane 36, it rocks the pointer 25 and lever 60 and slides the markercarriage 74: all in the same gen eral direction. so that like readingsof the tape and dial are in like general locations. When the markerframe M is swung out, its motion causes the teeth of the wheel segment(30 to slide out of and become disengaged from those of the pinion 260,and to render access to the tape mechanism unobstructed. When theframeis swung back to its normal position the marker carriage 74 isshifted (if necessary) so that its vertical axis and pencil 75 read onthe tape the same as the pointer does on the dial, and the teeth of thewheel segment slide into engagement with those of the pinion.

The operation of my marine speedometer or automatic reading andrecording direction-and-speed log follows: A standard exhauster bloweror reversible air pump is .operably connected, by a standard gearing,

adjusted by the set-screws 52 to the air friction in the pipe between itand the pump and to the modes of action of the engines when runningnormal and reverse, so that all the dials will read and the tapes recordsimilarly for the same engine-speeds. The dial A andtape 4 each have avertical axial space corresponding with rest, the sides are respectivelymarked Ahead and Astern and have four course graduations adapted toindicate the major speed graduations and inscribed with correspondinglegends. such as Full speed, Half and Slow. and the dial has finer speedgraduations correspond ing with knots, miles or it may be kilometers-Fig. 1 illustrates a case 1 hung to face fore. or starboard. Asillustrated therein in full lines, the pointer and carriage stand at theair pump, which causes a current of air to flow through the air pipesand thereby moves the vane 36, pointer 25 and pencil 75. When theengines run normally, the pointer and pencil are moved to the right andregister with Ahead and some speed graduations, as Slow, and the pointerregisters also with a fine speed graduation reading speed in knots (orother linear unit) per hour.

When the engines and air pump and the action of the latter on the vane36 are reversed, the pointer and pencil aremoved to the left, as shownin dotted lines in Fig. 1, and read Astern, Full (or other) speed andthe pointer shows the speed inunits. The tape 4: is fed uniformly andcontinuously by its gear connection with the clock and the pencil25,'combining its translations with the feed of the tape 4, tracesthereon a diagram which is a permanent record of the enginesperformance.

Generally the air-circuits will be open, each case 1 being piped to thepump from only onesocket, as 280 the other being left open, and readingsahead and astern will be caused, respectively by positive pressure and,suction on the vane 36; but in dirty ships, to protect the apparatus theair circuits may be closed, the sockets 280 and 280 ofeach case beingpiped respectively to opposite sides of the air pump.

Having thus described my invention, I claim:

' 1. In a marine speedometer adapted to indicate and record directionand speed ahead and astern by corresponding dips of a pointer and recorddiagrams, a case, an air duct in Said case, a movable abutment in saidduct adapted to be moved by varying air-tension on opposite faces, apointer operably connected with said movable abutment, and therebydipped in opposite directions to indicate respectively speed ahead andastern, a record tape, tape supporting means adapted to support saidtape, tapefeeding means adapted to cause afeed motion of said. tape, amarker adapted to mark said tape, and marker-shifting means operablyconnecting said movable abutment and marker and adapted to move saidmarker synchronously and in the same direction with said pointer.

2. In a marine speedometer adapted to in-- dicate and record directionand speed ahead and astern by corresponding dips of a.

pointer and record diagrams, a case, an air duct in said case, a closurein said duct adapted to be moved by varying air-tension on oppositefaces, a pointer operably connected with said closure and thereby dippedin opposite directions to indicate respectively speed ahead and astern,a record tape, tape supporting means adapted to support said tape,tape-feeding means adapted to cause a feed motion of said tape, a markeradapted to mark said tape, and markershifting means operably connectingsaid closure and marker and adapted to move said marker synchronouslyand in the same direction with said pointer.

3. In a marine speedometer, comprising a case, an air duct in said case,a closure pivotally mounted in said duct, a shaft axial on said closureextending through an opening in a wall of said duct, a pointer on saidshaft, a recording tape, tape.- supporting means adapted to supportsaidtape, tapefeeding means adapted to cause a feed-motion of said tape,a marker adapted to mark said tape, and" a marker-support on which saidmarker is movably mounted, the combination therewith of operating gearconnecting said shaft and marker and comprising a pinion on'said shaft,a pivotallymounted lever, a wheel-segment on one arm of said lever, andan operating connection operably connecting the other arm of said leverwith said marker.

4. In a marine speedometer comprising a case, an air duct in said case,a closure piv- -otally mounted in said duct, a shaft axial on saidclosure extending through an opening in a wall of said duct, a pointeron said shaft, a recording tape, tape-supporting means adapted tosupport said tape, tapefeeding means adapted to cause a feed-motion ofsaid tape, a marker-frame attached to said case, and a marker slidablymounted on said fram and adapted to mark said tape, the com inationtherewith of operating gear connecting said shaft and marker andcomprising a pinion on said shaft, a pivotally-mounted lever, awheel-segment on one arm of said lever, and an operating connectionoperably connecting the other arm of said lever with said marker.

5. In a marine speedometer comprising a case. an air duct in said case,a closure pivotally mounted in said duct, a shaft axial on said closureextending through an opening in a \vall'of said duct, a pointer on saidshaft, a recording tape, tapesupporting means adapted to support saidtape, and tape-feeding means adapted to cause a feedmotion 'of saidtape, the combination therewithof a marker-frame hinged to said case, amarker slidably mounted on said frame and adapted to mark said tape,operating gear connecting said shaftand marker and comprising a pinionon said shaft, a pivotally-mounted lever, a wheel-segment on one arm ofsaid lever, and an operating connection operably connecting the otherarm of said leve; with said marker.

6. In a marine speedometer adapted to, indicate and record direction andspeed ahead and astern by corresponding dips of a pointer and recorddiagrams, a case, an air duct in said case, a movable abutmentin saidduct adapted to be moved by varying air tensions on opposite faces, apointer operably connected with said movable abutment, and therebydipped in opposite directions to indicate respectively speed ahead andastern, a record tape, tape supporting means adapted to support saidtape, a pair of tape-feeding rolls, a clock movement, a gearing,operably and releasably connecting said clock movement with said rolls,a clutch in said gearing adapted to engage and disengage members of saidgearing, a marker adapted to mark said tape, a marker-support on whichsaid marker is movably mounted, and an operable connection between saidmarker and said movable abutment adapted to move said markersynchronously with and in the same direction with said pointer.

7 In a marine speedometer adapted to indicate and record direction andspeed ahead and aster-n by corresponding dips of a pointer and recorddiagrams, a case, an air duct in said case, a movable abutment in saidduct and nearly central in said case and adapted to be moved by varyingair-tensions on opposite faces, a pointer operably connected with saidmovable abutment, and thereby dipped in opposite directions to indicaterespectively speed ahead and astern, an indicator dial adapted to beread with said pointer, a record tape, tape-supporting means adapted tosupport said tape, marking means operably connected With said movableabutment and adapted to be moved thereby synchronously with and in thesame direction as said pointer, a pair of tapefeeding rolls, a clockmovement adjacent to said indicator dial, a clock dial, a gearingoperably connecting said clock movement and feed rolls and comprising atransmis sion shaft, a gear train operably connecting said shaft withsaid clock movement, a gear train operably connecting said shaft withsaid feed rolls, a clutch on said shaft adapted to connect anddisconnect it with and from a gear, a face plate adapted to close saidcase and inclose therein the aforesaid elements and glazed openings insaid face plate.

8. In a marine speedometer adapted to indicate and record direction andspeed ahead and astern by corresponding dips of a pointer and recorddiagrams, a case, an air duct in said case, a movable abutment in saidduct nearly central in and on the vertical axis of said case, a pointeroperably connected with said movable abutment and thereby dipped inopposite directions to indicate respectively speed ahead and astern, andoperable symmetrically relative to said axis, an axially locatedindicator dial adapted to be read with said pointer, an axiallylocatedrecord tape, tape-supporting means adapted to support said tape, markingmeans operably connected with said .mov-

able abutment and adapted to be moved thereby synchronously with and inthe same direction as said pointer, a pair of tapefceding rolls, a clockmovement adjacent to said indicator dial, a clock dial, a gearingoperably connecting said clock movement and feed rolls and comprising atransmission shaft, a gear train operably connecting said shaft withsaid clock movement, a gear train operably connecting said shaft withsaid feed rolls, a clutch on said shaft adapted to connect anddisconnect it with and from a gear, a face plate adapted to close saidcase and inclose therein the aforesaid elements and glazed openings insaid plate.

9. In a marine speedometer comprising a case, an air duct, a cylindricalsector in said duct, a closure axially and pivotally mounted in saidsector, a shaft axial on said closure and extending through an openingin a wall ofsaid duct, and a pointer on said shaft, the combinationtherewith of a record tape mechanism comprising a tape roll revolublymounted on said case, tape on said roll, a pair of tape feed rolls, aclock movement, a gearing operably connecting said clock mechanism withsaid feed rolls, a marking table on said case posterior to the traverseof said tape, a marker frame anterior to said table and to the traverseof said tape, a marker slidably mounted on said frame and operatingmeans operably connecting said shaft with said marker and adapted tomove said marker synchronously with and in the same direction as saidpointer.

10. In a reversible marine speedometer comprising a case, an air duct, acylindrical sector in said duct, a closure axially and pivotally mountedin said sector, a shaft axial on said closure and extending through anopening in a wall of said duct, a pointer on said shaft, and a recordtape mechanism comprising a tape roll revolubly mounted on said case,tape on said roll, a pair of tape feed rolls, a clock movement, and agearing operably connecting said clock mechanism with said feed rolls,the combination therewith of a marking table on said case posterior tothe traverse of said tape, a marker frame anterior to said table and tothe traverse of said tape and movable relatively thereto, a markerslidably mounted on said frame and co-acting marker operating members,one on said shaft and one mounted on said marker frame and operablyconnected with said marker, sa'id ooacting marker-operating membersadapted to be engaged and disengaged by motions of said marker ing in awall of said duct, anda pointer on said frame, a marking point slidablymount;

ed in said marker, and a spring adapted to press said point against saidtape and table, and operating means voperably connecting 15 said shaftwith said marker and adapted to move said marker.

CHARLES H. KENNEY.

Witnesses:

H. D. PENNEY, JOHN MORRIS.

